An MRI scan can be used to investigate almost any part of the body including the brain and spinal cord, bones and joints, breasts, heart and blood vessels and internal organs, such as the lungs and liver.

The waiting time in Tallaght Hospital in Dublin, which was at the centre of an X-ray scandal two years ago, is 19 months.

In 2010, it emerged that 58,000 X-rays at the hospital had not been read by radiologists over a four-year period and there had been two delayed diagnoses reported.

Other hospitals with long delays for routine MRI scans include Limerick Regional, the Mater and Galway University Hospital.

Separate figures from the Health Service Executive (HSE) show that 739 adults and 427 children are waiting to see a single ear nose and throat consultant who must service the whole of county Kerry.

The HSE also acknowledged the lengthy waiting times for patients in Kerry and Cork who need orthopaedic care.

There are more than 780 people waiting for more than three years to see an orthopaedic specialist in the two counties and 108 are in the queue for six to 12 months for admission to hospital for a procedure.